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Undertow with Waterlog:

UNDERTOW was stupid and mean even before the Power Core process turned him into a Combiner. He hates folks who think they’re smart, and now he has more than enough power to smash those guys to pieces.

Power up for the ultimate robot battles! Your UNDERTOW figure is already a virtually unstoppable opponent in his vehicle and robot modes. But his strength gets doubled when you factor in your WATERLOG figure and his four modes! Convert this MINI-CON ally figure to weapon accessories for him when he’s in jet boat vehicle mode or Commander mode. Then, convert your WATERLOG figure into an armor accessory for your UNDERTOW figure’s Power Up Mode! And the action doesn’t stop there. With this Power Core interchangeable robot combination system, MINI-CON figures and drone vehicles (sold separately) can attach to power up any Commander figure. Collect more packs and you can create tons of unique and fierce robot battler figure combinations!